Oil Refining Bleaching Process

Crude Oil→Weighing→Pre-mixing→Heating →Bleaching→Filtering→Primary Refining Oil→Safety Filtering→Decolorized Oil

The oil, after being measured, is preheated to a temperature of 80–90°C, and then fully premixed with activated bleaching earth before being sent to a decolorization tower for the decolorization process. The mixing of the oil and the activated bleaching earth is carried out under atmospheric pressure, while the pre-mixing takes place under high-temperature conditions. This method significantly reduces the oxidation of the oil caused by heating, thereby ensuring the quality of the oil.

Lipid Refining and Degumming Production Process

Phospholipids are an important component of plant cell structures. Phospholipids, often referred to as gums, are extracted along with crude oil from seeds and remain in the crude oil. In the oil processing industry, the content of phospholipids in the oil is expressed in terms of parts per million (ppm) of phosphorus. This is because there is a relationship between the phospholipid content and the corresponding phosphorus content in the oil.

Degumming of lipids is the process of reducing the phosphorus content in the oil to a very low level. The phosphorus content in the oil has a profound impact on the flavor, color, hydrolytic, and oxidative stability of refined, bleached, and deodorized oil, as well as on the refining yield. When the phosphorus content in the finished oil is high, it can lead to several process-related issues. For the following reasons, crude oil must be degummed before storage or transportation:

1. It can deposit or settle at the bottom of storage tanks, reducing the refining yield if the crude oil is stored for a long time without mechanical agitation.

2. It can accumulate at the bottom of shipping containers, increasing oil loss.

3. It increases refining losses.

The hydration degumming process is a widely used method for degumming. It involves adding a certain amount of hot water or electrolyte aqueous solution to the lipids, utilizing the hydrophilicity of substances like phospholipids. This causes colloidal impurities to absorb water, swell, and coagulate, allowing the gum to settle and separate from the lipids.

The key control points in the hydration degumming process are:

- Oil temperature

- Quantity of deionized water

- Residence time

- Mixing rate

- Vacuum drying level

- Vacuum drying of the gum